Answer: a:7 b:36 c:4
Step-by-step explanation:
the exponents are the amount of 0s you put behind the number.
ex: 10 to the power of 4: 10,000, 4 zeroes.
You're looking for the number 13 and 7 can go into.
You can use the listing method.
13: 13, 26, 39... and so on, and so on.
7: 7, 14, 21, 28, 35, 42, 49.... and so on.
An easier way to do it is to simply multiply 13 by 7.

13 and 7 can go into 91, evenly.
Hope this helped!
Answer:
Step-by-step explanation:
Uhm the third one number 3
1: Diameter - 16 in.
Radius - 8 in.
2: 37.68 in.
3: 20 yd.
4: 0.24 mi.
5: Both students are wrong because if you use the pi instead of its abbreviated form, then the answer is about 50.27 ft.
6: The circumference of a wheel is its diameter*pi.
For every 3 girls, there are 4 boys. if there are nine girls, that expands to three extra boys, because for every three theres an extra one. so there are 12 boys (9+3.) the final ratio, boys to girls, is 12:9.