Answer:
The answer is below
Explanation:
Newton's law of gravity states that the force between two bodies is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. The law is expressed by the formula:

The masses and distances for this question is in common units, Therefore the result would be in ratios
a) 4 MEarth / 2 MSolar / 3 AU
The force (F) = (4 * 3) / 3² = 4/3
b) 1 MEarth / 1 MSolar / 1 AU
The force (F) = (1 * 1) / 1² = 1
c) 1 MEarth / 2 MSolar / 2 AU
The force (F) = (1 * 2) / 2² = 1/2
If a mass of a neutron is 1 the electron mass is 0.00054386734 and it's charge is negative. Hope this helps! ;)
The reason why the snails are dead because the snails lack oxygen for it is a model of closed ecosystem. Another reason to this is that they lack abiotic factors that they need in surviving or as they live for the place that they are living lacks a lot and are not enough for them to last or survive. Lastly, the water could have not been a contributor for them to live for they may not be able to live in a water environment and could only dwell in land.
Answer:
Pressure of woman will be 
Pressure of the elephant will be 
Explanation:
We have given that mass of the woman m = 80 kg
Acceleration due to gravity 
Diameter of shoes = 1 cm =0.01 m
So radius 
So area 
We know that force is given F = mg
So 
Now we know that pressure is given by 
Now mass of elephant m = 5500 kg
So force of elephant = 5500×9.8 = 53900 N
Diameter = 20 cm
So radius r = 10 cm
So area will be 
So pressure will be 