Answer:
After 3 seconds
Step-by-step explanation:
Given

Required
Time the drop will hit the ground
When the drop hits the ground,

So, we have:

Rewrite as:

Expand

Factorize

Factor out 5t + 1

Split
or 
Solve for t
or 
Time cannot be negative.
So:

Answer:
42.84
Step-by-step explanation:
3.57*12=42.84
Answer:
$20
Step-by-step explanation:
multiply 100.00 x 5% which is 100x 0.05, then it will give you 5.
add 5, 4 more times which will give you 20
Answer: 20x^3 - 23x^2 - 4x + 4
Explanation:
Use distributive property:
(5x-2)(4x^2 - 3x-2)
= 20x^3 - 15x^2 - 10x - 8x^2 + 6x + 4
= 20x^3 - 23x^2 - 4x + 4