Janice - Please Help!!!

Find the exact value (either decimal or fractional form) of the first term of an arithmetic sequence if the sum of the first 100 terms is 7099.5 and the sum of the next 100 terms is 20799.

Find the only positive integer whose cube is the sum of the cubes of three positive integers immediately preceding it. Find this positive integer. Your algebraic work must be detailed enough to show this is the only positive integer with this property

Let m be any real number. Then the equation (m+1)^2 x-my-m^2-1=0 is a line. There is a unique point which this line goes through no matter what the value of m is; find the coordinates of this point.