Exclusive events, for OR we can add probabilities.
P(O or B) = 0.49 + 0.20 = 0.69
Answer 0.69
 
        
             
        
        
        
1)v/4-3=5
v-12=20
v=32
2)u/5+3=1
u+15=5
u=-10
3)6+z/9=9
54+z=81
z=27
4)-7+f/2=-1
-14+f=-2
f=12
5)9+w/4=-5
36+w=-20
w=-56
6)e/7-3=-5
e-21=-35
e=-14
7)-8+d/5=2
-40+d=10
d=50
8)u/5+3=6
u+15=30
u=15
9)f/-3+5=8
f-15=-24
f=-9
        
                    
             
        
        
        
Answer:
D
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
3.5 (D)
Step-by-step explanation:
focusing on the right side of the decimal, 5 rounds 5 to 6. 6 rounds 4 to 5. Anything 5 or above rounds up! So the .5 rounds 4 to 5, making the answer 3.5. So sorry if this doesn't make sense, its kind of hard to explain.
 
        
             
        
        
        
Answer:
c .3.3
Step-by-step explanation:
pH is the negative log of the molar hydrogen ion concentration.The equation to calculate pH is;
pH = -log10[H+]
pH = -log10(5.0 x 10-4)
pH = 3.30