Andrew is wanting to build a slide for his daughter's tree house in the backyard. The tree house is approximately 5 feet off the ground and he wants the slide to have a 30 degree angle with the ground. He will need to by 10 ft of sliding board.
The formula for depreciation is:

Where x = Initial value,
y= Amount after depreciation.
r= Rate of depreciation,
t = time (in years)
According to given problem,
x = 1040, y= 944 and t = 12 months =1 year.
So, first step is to plug in these values in the above formula, So,

944 = 1040 (1 -r)
Divide each sides by 1040.
0.907692308 =1 - r
0.907692308 - 1 = -r Subtract 1 from each sides.
-0.092307692 = -r
So, r = 0.09 or 9%.
Now plug in 0.09 in the above equation to get the depreciation equation. So,

So, 
b) To find the value of the bike after 5 months,
plug in t = 5 months= 5/12 = 0.41667 years in the above equation of depreciation.
So, 
y = 1040 * 0.961465659
y = 999.9242852
y = 1000 (Rounded to nearest integer).
Hence, the value of the bike after 5 months is $1000.
Since a product in maths means the result after multiplying numbers, you need to multiply 2 prime numbers and get 4.
If we look at the prime numbers: 2, 3, 5, 7, 11, etc, we see that the only number we can multiply to get 4 is 2, or, in other words, the only multiplication of prime numbers we can do to get four is 2*2=4.
One with 40cm being the side, 70 diagonal and 80 as the base so it is a right angle triangle
(1 7/10) / (3/5)
(17/10) / (3/5) =
17/10 * 5/3 =
85/30 =
2 5/6........yes, because 1 7/10 divided by 3/5 = 2 5/6...answer C