Answer:
total question =90
she obtained 75% of first 40 questions
- No. of question she got correct in first 40 = 75% * 40 = 30
2. in order to get 80% out of 90,
the no. of questions got correct by Ama = 80% * 90 = 72
3. As she already got 30 c0rrect in first 40 questions, the number of question she needs correct for remaining 50 = (72-30) = 42
percentage = 42/50*100% = 84%
Look at the picture it explains the answer
Answer:
Step-by-step explanation:
The different isotopes have different "half-lives" – the time it takes to lose half of its radioactivity. Pu-239 has a half-life of 24,100 years and Pu-241's half-life is 14.4 years. Substances with shorter half-lives decay more quickly than those with longer half-lives, so they emit more energetic radioactivity.
C bc the x is where the right angle is and the 2 sides of a right angle is going to be equal
