ok. the first part of the problem asked me to find the tension in the string. to do that i used Newtons second law where Tcos(theta)=mg
to find theta, i looksed at the picture, and since the radius(opposite side of the angle) and the hypotenuse were given, i applied sin, which was sin(theta)=r/l, which ledt to arcsin(.4/1) and i got theta to equal approximately 23 degrees. now for the second part of the problem, so far i could only think of finding the vlocity by the equation v=(omega)*(r), but then I am not sure how i would be able to convert velocity into rpm.