Answer:
Hematite and magnetite
Explanation:
Minerals such as Iron don’t occur alone due to its interaction with other elements. The Iron’s major source is usually through ores such as Hematite, Magnetite, limonite etc.
However Pure magnetite contains 72.4 percent iron and pure hematite contains 69.9 percent. They have the highest percentage of iron thereby making them the main sources.
Answer:
minimum angle is 128.69°
Explanation:
given data
player velocity with respect ground v1 = 3.5 m/s
ball velocity with respect himself v2 = 5.6 m/s
to find out
smallest angle
solution
we know ball velocity with respect field will be
ball velocity = v1 +v2
ball velocity = 3.5 + 5.6 = 9.1m/s
we consider angle that player hit ball is θ
then by as per figure triangle
cosθ = 
cosθ = 
θ = 51.31
so minimum angle is 180 - 51.31 = 128.69°
When smoke particles pass between the source of radiation and the detector the drop in radiation will be sufficient to tigger the alarm. <span />
Answer:
m = 4
Explanation:
We have,
You apply a force of 600 N to the branch which acts as a lever. It means it is input force, IF = 600 N
The rear of the truck weighs 2,400 N. It means it is output force, OF = 2400 N
The ratio of output force to the input force is equal to the mechanical advantage of the lever arm. It is given by :

So, the mechanical gain of the lever arm is 4.
Explanation:
One way of classifying stars is by their temperature .
or
Science strives to be able to describe how stars and planets form and evolve. This requires theories to describe the processes which include:
Star and planet formation
Star and planet composition
Stellar and solar system evolution
The nuclear processes happening inside stars
The scientific method means that all theories are put to the test. By measuring or calculating the temperature, age and composition of other planets and stars the theories can be tested. If observed values of these parameters are not predicted by theories, then the theories are wrong and need to be revised or replaced.