Answer:
Failure rate   = 20%
MTBF = 880 hours
Explanation:
given data 
batteries = 10 
tested = 200 hours
one failed = 20 hours
another fail at =  140 hours
solution
we know that Mean Time between Failures is express as = (Total up time) ÷  (number of breakdowns)    ....................1
so here Total up time will be 
Total up time = 200 × 10 
Total up time = 2000
and here 
Number of breakdown = 1 at 20 hour and another at 140 hour = 2
so it will be  = (Total up time) ÷ (number of breakdowns)      .......2
=   =  1000
   =  1000  
so here gap between occurrences is
gap between occurrences=  140 - 20 
gap between occurrences = 120 hour
and 
MTBF  will be 
MTBF = 1000 - 120
MTBF = 880 hours   
and 
Failure rate (FR)  will be 
Failure rate (FR) =  1 ÷ MTBF    ................3
Failure rate (FR) = R÷T     ......................4
as here R is the number of failures and T is total time 
so Failure rate (FR)  = 20%
 
        
             
        
        
        
Answer:
140m east
Explanation:
If East is positive then lets rephrase the problem into integers
 A truck moves +70 m, then moves -120m, and finally moves +90m.
So totally Displacement = +70-120+90= +140m
Since east is positive, the trucks resultant displacement is 140 m east of origin
 
        
             
        
        
        
Answer:
Yes
Explanation:
It is possible for sedimentary rocks to be converted to igneous rocks. Under conditions of high temperature and pressure, sedimentary rocks can be broken down into igneous rock by melting this rock type. 
When the rock is broken down, it forms melt which when cooled and solidifies will form igneous rocks. 
Sedimentary rocks are formed from the breaking down of pre-existing rocks through the action of weathering, erosion and sediment transportation. Within a basin, the sediments are compacted and lithified. 
When this is subjected to intense pressure and temperature, the rock hardens and might further break down to melt.
 
        
             
        
        
        
I believe the answer is Microwaves (just to clarify, not the oven). They're widely used for communications.<span />