In DCAB, If DB=38, What is DC? 38 45 52 112

C. 52°

Step-by-step explanation:

In ∆CAB, m<A = right angle = 90°

m<B = 38°

m<C + m<A + m<B = 180° (sum of ∆)

m<C + 90° + 38° = 180° (substitution)

m<C + 128 = 180

m<C = 180 - 128 (subtraction property of equality)

m<C = 52°

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)