5x+14<4 or -2(x-8)<-2

Step-by-step explanation:

5x+14<4 or -2(x-8)<-2

    -14 -14      -2x+16<-2

5x<-10                -16  -16

÷5  ÷5           -2x<-18

x<-2              ÷-2   ÷-2

                     x>9   (sign changes because you divide by a negative number)

x<-2 or x>9

d

step-by-step explanation:

i used the pitagoras theoreme

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

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