For question 1:
Part i)
2.6 x 2.6 = 6.76 cm squared
No unit conversions needed
Part ii)
1.2 dm = 1.2 / 1000000 = 0.0000012 cm
0.0000012 x 0.0000012 = 0.00000000000144 cm squared
Question 2:
16.5dm = 16.5/ 1000 = 0.0165 m
0.0165 x 0.0165 = 0.00027225 m squared
I hope this has helped
Alright so I got A=4, B=5 and C=9
A B C
+ A C B
----------
C B A
459
+ 495
--------
954
1985year ->275cell phones->100%
1994year -> x cell phones ->100%+360%
40% • (1994-1985)= 40% • 9= 360%
275 cell phone 100%
X cell phones. 100+360%=460%
x=275•460%/100%
x=12420/100
x=1265
99% sure this is a correct answer
x=275 • 460%/100%
x=12,420/100
x=1265
1994-1985= 9 yrs • 40%= 360%