Please help me :> i would love that ! :))

On a architect's drawing of a house, 1 inche representa 1.5

What is the number 321,000,000 in scientific notation? also what is the number? ?

Eric has challenged himself to walk 24,000 steps in 4 days. if eric walks the same number of steps each day, which function represents the number of steps eric still needs to walk to reach his goal with respect to the number of days since he started his challenge? a. y = 8,000x − 24,000 b. y = -8,000x + 24,000 c. y = 6,000x − 24,000 d. y = -6,000x + 24,000