Write these expressions as the square of a monomial.
81x4 (81x4 means 81x to the power of 4)
121a6 (the 6 means to the power of 6)
0.09y12 (The 12 means to the power of 12)
4/9b6 (The 6 means to the power of 6)
PLEASE HELP ASAP! WILL GIVE BRAINLIEST IF YOU SHOW STEPS!