Question 1: 2^2+4^2=c^2, 4+16=c^2,20=c^2, square root both sides, 4.5=c
Question 2: 3^2+5^2=b^2, 9+25=b^2, 34=b^2, square root both sides, 5.8=b
Question 3: 1.4^2+3.1^2=b^2, 1.96+9.61=b^2, 11.57=b^2, square root both sides, 3.4=b
Question 1 answer is D
Question 2 answer is C
Question 3 answer is B
Hope this helps and answers all your problems!!!!