10 days is twice the half-life. After 5 days, can expect

grams to remain; after another 5 days, you'd be left with

grams.
The answer could be (7+k)÷2
5n =70
5 x 14 = 70
hope this helped :)
7 is the right answer(please rate 5.0 stars so i can help other people out thanks)
Step-by-step explanation:
(cos 10° − sin 10°) / (cos 10° + sin 10°)
Rewrite 10° as 45° − 35°.
(cos(45° − 35°) − sin(45° − 35°)) / (cos(45° − 35°) + sin(45° − 35°))
Use angle difference formulas.
(cos 45° cos 35° + sin 45° sin 35° − sin 45° cos 35° + cos 45° sin 35°) / (cos 45° cos 35° + sin 45° sin 35° + sin 45° cos 35° − cos 45° sin 35°)
sin 45° = cos 45°, so dividing:
(cos 35° + sin 35° − cos 35° + sin 35°) / (cos 35° + sin 35° + cos 35° − sin 35°)
Combining like terms:
(2 sin 35°) / (2 cos 35°)
Dividing:
tan 35°