Final answer:
Precious Metals and Diamonds do not have a low value-to-weight ratio.a) Precious Metals
Step-by-step explanation:
The goods that do not have a low value-to-weight ratio are a) Precious Metals and d) Diamonds.
Precious metals like gold and silver have high value-to-weight ratios because they are valuable and relatively lightweight. Diamonds, on the other hand, have a high value-to-weight ratio due to their high value and small size. Grains and electronic gadgets have low value-to-weight ratios because they are relatively inexpensive but heavy.