1.Density of the material building the raft must be lower than the water.
<span>2. Material must not react with water. </span>
<span>3.Material must have high strength. </span>
<span>4.Raft must be wide in-order to avoid drawing in the river.</span>
Answer:
m = 788.2[kg]
Explanation:
The potential energy of a body is defined as the product of mass by gravitational acceleration by height. And it can be calculated by means of the following equation.

where:
Epot = potential energy = 63405 [J]
m = mass [kg]
g = gravity acceleration = 9.81[m/s²]
h = elevation = 8.2[m]
Now replacing:
![63405=m*9.81*8.2\\m=788.2[kg]](https://tex.z-dn.net/?f=63405%3Dm%2A9.81%2A8.2%5C%5Cm%3D788.2%5Bkg%5D)
Answer:
Resulting Change in the Magnetic Flux 
Explanation:
Thanks!
We're told that the planets have EQUAL MASS.
If that's true, then the strength of the gravitational forces between
each planet and the star depends only on the distance between
them ... the farther a planet is from the star, the smaller the
gravitational forces are IF we're talking about planets with
equal masses.
Planet-X is closer to the star, and Planet-Y is farther from it.
From this we know that the gravitational forces between the
star and Planet-X are greater, and the forces between the star
and Planet-Y are smaller.
'A' says this.
'B' is totally absurd, because it talks about gravity repelling things.
'C' says exactly the opposite for the two planets.
'D' says that distance doesn't matter. We know this is absurd,
simply because we're never pulled toward Jupiter in our daily life.
I believe it is A bit not completely sure