a) \( 8.3:(-4)-(12-5.3)+30:(-5)-[(-15):(-3) \cdot 6-4.8]= \) b) \( -100:(20+5) \cdot(-3)+8 \cdot(-7+2)+(14-8) \cdot 7= \) c) \( [12:(10-2 \cdot 2)+(-8+5-1)] \cdot 3+(9 \cdot 2-15) \cdot 6= \) d) \( 5 \cdot(-3+7)+4 \cdot(-8): 2-(5+6-9)= \) e) \( [(-420): 7 \cdot(-5)] \cdot(-3)+1000:(-10): 5 \cdot(-2)= \) f) \( -18:(7-3 \cdot 3+1)+(-15+25) \cdot(-8)= \) g) \( (-45: 5-64: 8) \cdot 2+(-9+5) \cdot(10-2+3)= \)

To tackle these expressions, visualizing the operations step-by-step can make things more engaging! Start with divisions and multiplications before you sum or subtract. But beware of those pesky parentheses that can lead you off track if not handled properly! For instance, remember that negative numbers can do a dance that might catch you off guard. Double check your signs, especially during subtraction or when you're multiplying two negatives—they can turn into a positive, making everything suddenly brighter!