WEST CHENNAI SAHODAYA CLUSTER
COMMON EXAMINATION
CLASS XII
COMPUTER SCIENCE -083/1
MARKING SCHEME
MAX. MARKS: 70 DURATION: 3 HRS.
SECTION – A ( 21 x 1=21)
1. True
2. a) @EVATE YOURS@F
3. True
4. ‘*’.join(a)
5. b)orl
6. iterator
7. b) [ [10,10,10],4]
8 c) returns the identity of object
9. d) return number
10. F.readline(50)
11. c) count(*)
12. c) UPDATE
13. sector
14. False
15. d) When 1 == "1" is executed, exception is raised
16. d) HTTPS
17 a) add a column
18. b) Co-axial
19. Circuit.
20. (A) Both A and R are true and R is the correct explanation for A
21. (C) A is True but R is False
SECTION– B (7 x 2 = 14)
22. i) B=2345
print(B//1000+B%10)
ii) print(S.count(‘c’)
OR
print(S.find(‘c’))
23. i) ['demonstrate']
ii) L1.extend(L2) OR sorted(L1+L2)
24. a) Black*White* b) Black* d) No output
Maximum value=2, minimum value =0
25. i) Ravi's code is incorrect because in Python, default arguments must come after all non-default
arguments. The parameter Time is a non-default argument but comes after Rate, which is a
default argument. This violates Python's rules for function arguments.
To fix the issue, all non-default arguments should appear before default arguments. Here's the
corrected code:
def CalculateInterest(Principal, Time, Rate=0.06):
# code
ii) The global keyword allows a function to access and modify a global variable directly, rather
than creating or working with a local copy.
26. i) a) Ecode
OR
b) NOT NULL
ii) a) Alter table HRDATA add REMARKS varchar(100) ;
OR
b)Alter table HRDATA drop column Remn;
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27. The MODIFY clause in an ALTER command in SQL is used to alter the structure of a table by
changing the definition of an existing column. MODIFY clause can be used to:
Change the data type of a column.
Adjust the size of a column.
Add or remove constraints (like NOT NULL or DEFAULT) to a column.
Ex. ALTER TABLE table_name MODIFY column_name new_definition;
28. a) Bus topology requires fewer cables and no central device like a hub or switch, which makes it
cheaper to set up compared to Star topology, In a Bus topology, devices are connected in a
linear manner to a single backbone cable. This makes it easier to install and expand for small
networks. In contrast, Star topology requires separate cables for each device to connect to the
central hub, which can make installation more complex and time-consuming.
OR
b) Wired Transmission medium - Optical Fiber Cable: It offers significantly higher bandwidth and
data transmission speed.
Wireless Transmission medium – Microwave: Microwaves have higher frequencies than other
types of waves, which allows for faster data transmission rates.
SECTION – C (3 x 3 = 9)
29. A) def DISPLAY():
f=open(“Article.txt”)
max=0
for i in f.read().split():
if i==i[::-1]:
l=len(i)
if l>max:
max=l
k=i
print(k)
OR
B) def DISPLAY():
f=open(“Article.txt”)
max=0
for i in f:
j=i.split()
if j[1].startswith(‘7’):
print(i)
30. A) Upper case count : 3
Lower case count : 15
OR
B) The new string is: string76STR
31. A) hostel =[]
def Push_element(L):
for i in L:
hostel.append(i)
def Pop_element():
while hostel!=[]:
print(hostel.pop())
else:
print(“Stack Empty”)
OR
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B) stack=[]
def Push(D):
for i in D:
if D[i]>=900000:
stack.append( [ i, D[i] ])
def pop():
while stack!=[]:
L=stack.pop()
print(L[0],L[1])
SECTION – D (4x 4=16)
32. A) Write SQL Queries for the following questions:
i) select sum(SALARY) from Employee where PROJECT is not NULL;
ii) select count(*) from Employee group by PROJECT;
iii) select distinct PROJECT from Employee;
iv) select NAME from Employee where DOB> “1992-10-31”;
OR
B) Write the output of the queries (i) to (iv) based on the table Employee:
i)
NAME PROJECT
Ranjan P01
Muneera P01
Alex P02
Akhtar P04
Satyansh P04
ii)
NAME SALARY
Ranjan 150000
Akhtar 75000
iii)
NAME DOB DOJ
Ranjan 1990-07-12 2015-01-21
Akhtar 1992-06-21 2015-02-01
Muneera 1996-11-15 2018-08-19
iv)
min(DOJ) max(DOB)
2015-01-21 1996-11-15
33. import csv
def Television():
F=open( “Inventroy.csv” ,’r’)
wr=csv.reader(F)
l=[]
cost=0
for i in wr:
l.append(i)
for j in range(1, len(l)):
if i[1]==”Television”:
print(i)
cost+=int(i[3])
print(cost)
F.close()
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34. i) select sum(M_Qty), M_Name from MOBILEMASTER natural join MOBILESTOCK
group by M_Id;
ii) select M_Supplier from MOBILEMASTER natural join MOBILESTOCK
where M_Company =”Nokia”;
iii) update MOBILEMASTER set M_Price=M_Price-2000
where M_Mf_Date between “2011-01-01” and “2013-12-31”;
iv) A) select sum(M_price*M_Qty) from MOBILEMASTER natural join MOBILESTOCK
where M_Company=”Micromax”;
OR
B) alter table MOBILEMASTER add discount int;
35. import mysql.connector as ms
con=ms.connect(host=”localhost”, user=”root”, password=”tiger”, database=”school”)
cur=con.cursor()a
n=int(input())
for i in range(n):
rno=int(input())
name=input()
dob=input()
fee=float(input())
sql=”insert into Student values({},’{}’, ‘{}’,{})”.format(rno,name,dob,fee)
cur.execute(sql)
con.commit()
cur.execute(“update Student set fee=fee+fee*0.1”)
con.commit()
SECTION – E ( 2 x 5 =10)
36. i) import pickle
def input_students():
f=open(“Result.dat”,’ab’)
c = []
n = int(input())
for i in range(n):
s_id = int(input())
s_name = input()
gname = input()
points = float(input())
result=input()
c.append([s_id, s_name, gname, points, result])
pickle.dump(c,f)
f.close()
ii) def read_students():
f=open(“Results.dat”,’rb’)
try:
while True:
m=pickle.load(f)
for i in m:
if i[4]==”Won”:
print(i)
except EOFError:
f.close()
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iii) def update_results():
u=[]
f=open(“Results.dat”,’rb’)
try:
while True:
m=pickle.load(f)
for i in m:
if i[3]>50:
i[4]=”Won”
u.append(i)
except EOFError:
f.close()
f=open(“Results.dat”,’wb’)
pickle.dump(u,f)
f.close()
37. a)
b) Main Building as it has more number of computers.
c) i) Switch/Hub – recommended in all buildings as the number of computers is more.
ii) Repeater – recommended between finance and academic since the distance is 70m
d) Modem is needed if internet connection is to be provided to all the blocks and to be place in
Main building.
e) i) LAN
OR
ii) Ethernet cable or Twisted pair cable
***************END OF PAPER***************
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