Answer:

mass = 3.645 g
volume = 9×9×9
= 729 cm³
density = 3.645/729
= 0.005 gcm^-3
Step-by-step explanation:
the volume is 729 cm³ cause the given height is 9cm and it is a cube. cube has equal sides so their lengths are the same.
volume = length × height × width
the formula is a_{1}+(n-1) d
so a_{1} would be the first number in the sequence, which would be 13 in problem 9.
13+(n-1)d
then you put in n, which is 10 (it represents which number in the sequence you're looking for, for example 16 is the second number in the sequence)
13+(10-1)d
then you find the difference between each number, represented by d which in this case is 3
13+(10-1)3
13+(9)3
13+27=
40
Answer:
106.1 ft/s
Step-by-step explanation:
You know the diagonal of a square is √2 times the length of one side, so the distance from 3rd to 1st is 90√2 feet ≈ 127.2792 ft.
The speed is the ratio of distance to time:
speed = distance/time = 127.2972 ft/(1.2 s) ≈ 106.1 ft/s.
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In case you have never figured or seen the computation of the diagonal of a square (the hypotenuse of an isosceles right triangle), consider the square with side lengths 1. The diagonal will cut the square into halves that are isosceles right triangles with leg lengths 1. Then the Pythagorean theorem can be used to find the diagonal length d:
d² = 1² + 1²
d² = 2
d = √2
Since this is the diagonal for a side length of 1, any other side length will serve as a scale factor for this value. A square with a side length of 90 ft will have a diagonal measuring 90√2 ft.
This is all middle school stuff.
First do the powers. 3 power plus -5 power equals to -2 power.
2 x 5 is 10. So, it's 10 to the power of -2.