Answer:
Step-by-step explanation:
Start with where it tells you the value of x. The value of x is 3. That's given by f(x) = f(3)
Next see which one of the functions you use. x > 0 is given by x^4 - 7. Since 3 is greater than zero you use x^4 - 7
f(3) means that wherever you see an x on the right side, you put a 3.
f(x) = x^4 - 7
f(3) = 3^4 - 7
f(3) = 81 - 7
f(3) = 74
The answer to your question is 102
(I think you need a-e, if not let me know and I will edit accordingly)
a: Divide both sides by 4
cm -> 12:8
3:2
b: Convert and divide both sides by 3
cm -> 150:9
50:3
c: Convert and divide both sides by 20
cm -> 100:80
5:4
d: Convert and divide both sides by 4
months -> 4:12
1:3
e: Convert and divide both sides by 250
g -> 2000:250
8:1
Hope this helps, have a nice day :)