PLZZZZZZZZZZZZZZZZZZZZZZ HELPTHIS DUE RIGHT NOWPLZZ HELP!!!

1.Write an addition expression using decimals that equals -0.5

2. Solve the following expressions.(Show your steps for subtraction
A. - 3.1+(-0.35)
B. - 7.34-(-5.51)
C.20.25+(-5.51)