## Solution:

### To solve this problem you have to employ `using`

with templates

### Code:

```
#include <vector>
template <typename T>
using DataElement = std::vector<T>;
template <typename T>
using DataVector = std::vector<DataElement<T>>;
int main()
{
DataVector<double> data;
data.emplace_back(DataElement<double>{ 1.0f, 1.0f });
data.emplace_back(DataElement<double>{ 1.1f, 1.1f });
}
```

Hopefully, you are able to solve this problem.