Working with standard form

This task is about calculating numbers in standard form.
 
Write your answers for a) to d) in standard form.
  
a)
A satellite travels 4.0 × 104 kilometres when it orbits the Earth once. How many kilometres would the satellite travel after orbiting the Earth 1000 times?
 
Optional space for working
 
 
 
 
Standard form: _____________________ km

 

 
b)
 
The population of Christchurch city is 3.78 × 105 and the population of Wellington city is 2.15 × 105. What is the total population of Christchurch and Wellington cities?
 
Optional space for working
 
 
 
 
Standard form: _____________________ 

 

 
c)
 
New Zealand has 2.89 × 105 beehives and the average hive has 5.0 × 104 bees. What is the total number of bees in New Zealand?
 
Optional space for working 
 
 
 

Standard form: _____________________

 

     
d)
The Sun has a mass of 2.0 × 1030 kilograms and the Earth has a mass of 6.0 ×1023 kilograms. What is the Sun's mass divided by the Earth's mass?
 
Optional space for working 
 
 
 
 
Standard form: _____________________