At city community college, every freshman must take English 101. The English department wants to know whether students who take
this class and their second semester get better grades than students who take the class in the first semester which principle of experimental design can the English department best used to include a variety of students in both the first and second semester treatment groups of the study
19. The balloon hits the ground means -16t2+25t+3=0 After you solve the equation, there are 2 solution ~1.67 or ~-0.11 (the time can not be negative) so the solution is 1.67s 20.substitute t=1 to the function -16(1)2+25(1)+3=-16+25+3=12 ft. So the height is 12ft when t=1
