Let's handle this case by case.
Clearly, there's no way both children can be girls.  There are then two cases:
Case 1: Two boys.  In this case, we have 13 possibilities:  the first is born on a Tuesday and the second is not (that's 6 possibilities, six ways to choose the day for the second boy), the first is not born on a Tuesday and the second is (6 more possibilities, same logic), and both are born on a Tuesday (1 final possibility), for a total of 13 possibilities with this case.
Case 2: A boy and a girl.  In this case, there are 14 possibilities:  The first is a boy born on a Tuesday and the second is a girl born on any day (7 possibilities, again choosing the day of the week.  We are counting possibilities by days of the week, so we must be consistent here.), or the first is a girl born any day and the second is a boy born on a Tuesday (7 possibilities).
We're trying to find the probability of case 1 occurring given that case 1 or case 2 occurs.  As there's 13+14=27 ways for either case to occur, we have a 13/27 probability that case 1 is the one that occurred.
        
                    
             
        
        
        
Answer:
d. Variable ratio
Step-by-step explanation:
We are asked to determine that gambling at a slot machine is an example of which reinforcement schedule. 
Let us see our given choices one by one.
a. Fixed ratio
We know that in fixed ratio schedule, reinforcement is delivered after the completion of a number of responses. An example of fixed ratio is a reward to every 6th response.
b. Fixed interval
We know that in fixed interval schedule the first response is rewarded only after a specified amount of time has elapsed. An example of fixed interval schedule is weekly paycheck.
c. Variable interval
We know that in variable interval schedule, the reinforcement is delivered at changing and unpredictable intervals of time. 
d. Variable ratio
In variable ratio schedule, a response is reinforced after an unpredictable number of responses. Gambling and lottery are examples of variable ratio.
Therefore, option 'd' is the correct choice.
 
        
             
        
        
        
Answer: She should buy 3 bottles
Step-by-step explanation: 1 quart = 4 cups. 4x3=12
 
        
                    
             
        
        
        
Answer:
<h2>a)  10⁶metres</h2><h2>b) 10¹⁸metres</h2>
Step-by-step explanation:
Given One terameter equals 10¹² meters. One micrometer equals 10⁻⁶ meter, one nanometer equals 10⁻⁹meter;
a) The product of one terameter and one micrometer will be expressed as;
10¹²  * 10⁻⁶
Since the both have the same base, we will add their power according to one of the law in indices as shown
10¹²  * 10⁻⁶ = 10⁻⁶⁺¹²
= 10⁶metres
b) The quotient of one terameter and one micrometer can be gotten by taking their ratio as shown below;
Note that when taking the quotient, the power are subtracted
