Answer:
x - Jack's age
y - Susan's age
Jack is 27 years older than Susan.
In 5 years he will be 4 times as old as she is.
Jack is 31 years old and Susan is 4 years old.
Answer:

Step-by-step explanation:
The standard form is called the scientific notation expressed generally as;

A is an integer between 1 and 10
n is ant integer or fraction
Given the decimal value 98.704, we ill shift the decimal point to the back once to have;
98.704 = 
<u>Note the when the decimal point is shifted backwards the value of n is always positive</u>. Hence the expansion in power of 10 is 
Power is work done per time and work done is force times distance. The power is found by multiplying the force(20N) and the distance(5m) and dividing the product by the time(5s)
(20*5)/5=20Nm/s OR 20 watts.
Therefore the power needed is 20 watts.