Answer:
The height is 20 cm.
Step-by-step explanation:
First, we have to know that the volume formula is V = πr²h and the base area of cylinder is a circle. So we can let πr² be 77 cm² . Then we have to substitute the following values into the formula :



Let πr² be 77,
Let v be 1540,




Answer:

Step-by-step explanation:
we know that
<u><em>Combinations</em></u> are a way to calculate the total outcomes of an event where order of the outcomes does not matter.
To calculate combinations, we will use the formula

where
n represents the total number of items
r represents the number of items being chosen at a time.
In this problem

substitute

simplify


