Answer:
24
Step-by-step explanation:
To find the % of something all you have to do is convert 30% to a decimal (.3) and times it by the number you want the percent out of (80) so 80 *.3= 24
surface area of cuboid=2(l*b+b*h+h*l)
=2(15*15+15*7+7*15)
=2(225+105+105)
=2*435
=870
15
