Answer this plz I’ll mark brainliest:)

7.5

Step-by-step explanation:

7.5 is the smallest. 7.51 is bigger by 0.01, 7.501 is bigger by 0.001 and 7.5 with a dot on top means that the number 5 repeats itself indefinately after the comma so it is like if we wrote 7.55555555 and the 5 kept going on forever

step-by-step explanation:

the original amount doesn't ''re just looking for the time it takes for 1/2 of the substance to we have

(1/2) =)     take the ln   of both sides

ln (1/2)   = )   and we can write

ln(1/2) = ) lne     and lne   = 1     so we have

ln(1/2) = -.1092t     divide both sides by -.1092

t = ln(1/2)/-.1092 = about 6.347 days = about 6.3 days (rounded)