you are taking the following test:

Grade: 8,    Subject: Math,    Topic: Number and Number Sense Negative exponents and manipulation
 Question 1: What is the 50% of 2.5 × 10−4? 1.25 × 10−2 2.25 × 10−4 1.25 × 10−4 5.0 × 10−2
 Question 2: 0.0001 × 3.23 × 10−2 = ________ 3.23 × 10+2 3.23 × 10+4 323.0 × 10−6 3.23 × 10−6
 Question 3: A 2.3 × 10−3 cm long nano fiber is divided into 100 parts. What is the length of a divided part? 2.3 × 10−2 cm 2.3 × 10−5 cm 2.3 × 10−6 cm 0.23 × 10−5 cm
 Question 4: Old semiconductor technology was capable of producing 90 × 10−9 m wide lines. Latest technology has further reduced the width by 50%. How wide lines can be produced now? 45 × 10−9 m 90 × 10−9 m 2.5 × 10−9 m 35 × 10−9 m
 Question 5: Light takes about 5.4 × 10−6 seconds to travel one mile in a vacuum. How long will it take the light to travel only one twentieth of a mile? 5.4 × 10−7 seconds 2.7 × 10−7 seconds 2.7 × 10−6 seconds 2.7 × 10−5 seconds
 Question 6: 4.5 × 10−7 × 2.0 × 10+4 = __________ 3.5 × 10−11 3.5 × 10−3 9.0 × 10−3 9.0 × 10−28
 Question 7: What is two seventh of 2.8 × 10−6? 4.0 × 10−7 0.8 × 10−6 8.0 × 10−7 8.0 × 10−6
 Question 8: A strobe light flashes for one microsecond and then pauses for one microsecond in one flash cycle. Calculate time to complete 10,000 cycles? one microsecond = 10−6 second, one millisecond = 10−3 second. 20 millisecond 1 millisecond 100 microsecond 20 microsecond
 Question 9: What is 6% of 3.9 × 10−4? 2.34 × 10−3 2.34 × 10−7 2.34 × 10−5 2.34 × 10−6
 Question 10: What is two-third of 60% of 5.7 × 10−8? 1.14 × 10−9 3.42 × 10−8 2.28 × 10−9 2.28 × 10−8