The access code for a cars security system consists of four digits. the first digit cannot be 1 and the last digit must be odd. how many different codes are available

7

step-by-step explanation:

-60.75

step-by-step explanation:

just add the numbers then put the negative sign on it

step-by-step explanation:

i think its about 8

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

source: