The formula for this problem that we will be using is:
F * cos α = m * g * μs where:F = 800m = 87g = 9.8
cos α = m*g*μs/F= 87*9.8*0.55/800= 0.59 So solving the alpha, find the arccos above.
α = arccos 0.59 = 54 ° is the largest value of alpha
Answer:

Explanation:
The apparent brightness follows an inverse square law, therefore we can write:

where I is the apparent brightness and r is the distance from the Sun.
We can also rewrite the law as
(1)
where in this problem, we have:
apparent brightness at a distance
, where
million km
We want to estimate the apparent brightness at
, where
is ten times
, so

Re-arranging eq.(1), we find
:

Answer:
m=ρV
V=4/3 * pi * r3
V=1.3 * 3.14 * 3.9^3
V=242.14 cm^3
m=7.58 * 242.14
m=1.8 kG
Explanation:
1. We calculate volume for sphere.
2. Then we calculate mass of sphere.
Answer:
The height of the tree is three (3) deep
Explanation:
It's 3 deep
Under 129, comes 125 and 685;
Under 125, comes 52 : Under 685, comes 511;
Under 52, comes 46 : Under 511, is 601.
This is illustrated below.
129
∧
125,685
|,|
52,511
|,|
46,601