A data archivist needs to transfer 30 datasets to storage units, each with a capacity of $1.5\text{ MB}$. 4 of the datasets are $1.0\text{ MB}$ each, 8 of the datasets are $0.7\text{ MB}$ each, and the rest take up $0.3\text{ MB}$ each. No dataset can be split across multiple storage units. What is the minimum number of storage units required to store all 30 datasets?