I NEED HELP WHOEVER ANSWERS CORRECTLY WILL GET BRAINLIEST
.(9x 10^-3)^2

simplify. write in scientific notation
a 8.1x10^-5
b 81x10^-4
c 81x10^-3
d 8.1x10^-6
Evaluate 1/2a^-4b^2 for a =-2 and b=4
a2
b 1/2
c3
d4
is the following statement always, never, or sometimes true?
a number raised to a negative exponent is negative?
A always
B never
C sometimes

The anwser cause i do not understand just plez

The serenity and the mystic are sail boats. the serenity and the mystic start at the same point and travel away from each other in opposite directions. the serenity travels at 16 mph and the mystic travels at 19 mph. how far apart will they be in 3 hours?

Sara has been reading about different types of financial grants, including federal pell grants, academic competitiveness grants, smart grants, and teach grants. which statement about these grants is true? filling out a fafsa will not her apply for these grants. she will not have to pay back any funds she receives from these grants. these grants only go to students with less than a 3.0 gpa. she will have to pay back all the funds she receives from these grants.