Answer:
Step-by-step explanation:
3/4 + 3/4 + 3/4 + 3/4 = 12/4 = 3. She will walk 3 miles in an hour.
Answer:
5
10
4
7
Step-by-step explanation:
Apply the value of x into the expressions:
3(5) - 10 = 15 - 10
= 5
5² - 15 = 25 - 15
= 10
5(5) - 21 = 25 - 21
= 4
5 + 10 - 8 = 15 - 8
= 7
Answer:
The rate of change is 
ft^(2)/min
Step-by-step explanation:
The area of a circle is given by the following equation:
To solve this question, we have to realize the implicit differentiation in function of t. We have two variables, A and r. So
We have that:
.
We want to find 
So
Since the area is in square feet, the rate of change is in ft^(2)/min.
So the rate of change is ft^(2)/min
1 electron has a mass of 9.1 X 10-31 kg. How many electrons n does it take to make 1 kg?
(1 e)/(9.1 X 10-31 kg) = n/(1 kg)
So, n = 1.10 X 1030 electrons
Each electron has a charge of 1.6 X 10-19 C, where C stands for Coulombs. So, the n electrons have a charge of q = ne = (1.10 X 1030 electrons) X (1.6 X 10-19 C/electron) = 1.76 X 1011 C.
Let the number be x and 2x-5 from the above given condition
x+2x-5=70
or
3x=75 s0 x=25
Hence, the number are 25 and 45
