Which of the following always exist between two objects having mass ● elastic force ● contact force ●gravitational force ●magnetic force

Gravitational force as gravity is forever...

Both objects have gravitational force because how much gravitational force an object has is based on its mass. This is why all planets orbit the Sun, because it is bigger than the planets.

The answer is : v = 55 + 8m plug in m = 25 v = 55 + 8(25) = 255 25 minutes after baxter begins filling the tank, the volume of water in the tank will be 255 gallons. slope: m = 8 gal/min for every min the water is on, the volume of water in the tank increases by 55 gallons. y-intercept: 55 (0,55) the initial volume of water in the tank was 55 gallons.

It depends on the subject for me. some exams are easier than others so i usually go through it and answer questions i know based on my general knowledge, then double check after. going through the lesson can a lot  because the exams can be  very lesson-specific, but sometimes they are ridiculously long so a lot of people don't take the time. i did find that, when i went through the lessons, i was making 100's on my exams vs strictly using + the internet and  i make 90's.